Field of Invention
The invention relates to a method of operating a heat exchange system and to a heat exchange system
Background Information
Methods of operating a heat exchange system and heat exchange systems are already known and can be found in a plurality of technical applications. Heat exchange systems are used in refrigeration plants such as in common domestic refrigerators; in air-conditioning systems for buildings or in vehicles of all kinds, above all in motor vehicles, in aircraft and in ships; as water coolers or as oil coolers in combustion engines; as condensers or as evaporators in refrigerant circuits; and in further innumerable different applications which are all well-known to the skilled person.
In practical use, a heat exchange system comprises at least one heat exchanger and one fan. The heat exchanger is in this respect connected to a circuit which contains a heat transfer fluid, i.e. a heat transfer medium, for example a coolant, with the heat exchanger taking up or transferring heat. The heat transfer fluid can in this respect be a coolant, water, water with glycol or a gas, for example ammonia or CO2. The transport fluid outside the heat exchanger, e.g. water, oil or frequently simply the environmental air, can take up thermal energy from the heat exchanger or transfer it to the heat exchanger and is therefore either correspondingly heated or cooled in this respect. The transport fluid usually has a substantially lower heat transfer coefficient than the heat transfer fluid circulating in the heat exchanger.
This is compensated by very different heat transfer surfaces for the two media. The heat transfer fluid having the high heat transfer coefficient therefore flows in a pipe or in an extruded section which, on the outer side, has a greatly enlarged surface due to one or more ribs or fins, for example sheet metal parts, at which surface the heat transfer takes place with the transport fluid, for example with the environmental air.
One possibility of sensibly classifying the heat exchangers consists of making a distinction based on the design and/or the manufacture of the different types of heat exchangers.
A widespread embodiment is the fin heat exchanger. In the simplest case, a fin heat exchanger comprises a pipe for conducting the heat transfer fluid and a plurality of fins which are connected to the pipe and which are in communication with a transport fluid in operation. The fin heat exchanger is particularly expedient when the transport fluid is gaseous and comprises environmental air since the latter has a comparatively low heat transfer coefficient which can be compensated by a correspondingly large surface of the fins.
The manufacture of these so-called fin heat exchangers takes place in accordance with a standardized process which has long been known: The fins are stamped using a press and using a special tool and are laid in packets with respect to one another. The pipes are subsequently pushed in and widened either mechanically or hydraulically so that a very good contact, and thus a good heat transfer, arises between the pipe and the fin. The individual pipes are then connected to one another, frequently soldered to one another, by bends and manifolds.
A heat exchange system and methods of operating a heat exchange system are known from WO 2011/033444 A1, wherein one or more actual values of the heat exchange system are received and/or wherein one or more desired values of the heat exchange system are adjusted by a control unit. The control unit can in this respect, for example be in signal communication with one or more sensors and/or actuators of the heat exchange system, for example sensors and actuators at the heat exchanger or at a fan of the heat exchange system. An actual value of a sensor can be received by the control unit in this respect, the actual value can be compared with a desired value by the control unit and the desired value can be adjusted at an actuator by the control unit.